do not abort() when memory is insufficient. this fixes issue #244

qemu/exec.c

@@ -1083,6 +1083,7 @@ static ram_addr_t ram_block_add(struct uc_struct *uc, RAMBlock *new_block, Error
     return new_block->offset;
 }
 
+// return -1 on error
 ram_addr_t qemu_ram_alloc_from_ptr(ram_addr_t size, void *host,
         MemoryRegion *mr, Error **errp)
 {
@@ -1092,6 +1093,9 @@ ram_addr_t qemu_ram_alloc_from_ptr(ram_addr_t size, void *host,
 
     size = TARGET_PAGE_ALIGN(size);
     new_block = g_malloc0(sizeof(*new_block));
+    if (new_block == NULL)
+        return -1;
+
     new_block->mr = mr;
     new_block->length = size;
     new_block->fd = -1;

qemu/memory.c

@@ -36,6 +36,9 @@ MemoryRegion *memory_map(struct uc_struct *uc, ram_addr_t begin, size_t size, ui
     MemoryRegion *ram = g_new(MemoryRegion, 1);
 
     memory_region_init_ram(uc, ram, NULL, "pc.ram", size, perms, &error_abort);
+    if (ram->ram_addr == -1)
+        // out of memory
+        return NULL;
 
     memory_region_add_subregion(get_system_memory(uc), begin, ram);
 

qemu/util/error.c

@@ -40,7 +40,7 @@ void error_set(Error **errp, ErrorClass err_class, const char *fmt, ...)
     err->err_class = err_class;
 
     if (errp == &error_abort) {
-        abort();
+        // abort();
     }
 
     *errp = err;
@@ -75,7 +75,7 @@ void error_set_errno(Error **errp, int os_errno, ErrorClass err_class,
     err->err_class = err_class;
 
     if (errp == &error_abort) {
-        abort();
+        // abort();
     }
 
     *errp = err;
@@ -160,7 +160,7 @@ void error_free(Error *err)
 void error_propagate(Error **dst_errp, Error *local_err)
 {
     if (local_err && dst_errp == &error_abort) {
-        abort();
+        // abort();
     } else if (dst_errp && !*dst_errp) {
         *dst_errp = local_err;
     } else if (local_err) {

uc.c

@@ -593,7 +593,11 @@ uc_err uc_mem_map(uc_engine *uc, uint64_t address, size_t size, uint32_t perms)
         }
         uc->mapped_blocks = regions;
     }
+
     uc->mapped_blocks[uc->mapped_block_count] = uc->memory_map(uc, address, size, perms);
+    if (uc->mapped_blocks[uc->mapped_block_count] == NULL)
+        return UC_ERR_NOMEM;
+
     uc->mapped_block_count++;
 
     return UC_ERR_OK;